Vascular-Resident CD169-Positive Monocytes and Macrophages Control Neutrophil Accumulation in the Kidney with Ischemia-Reperfusion Injury

Monocytes and kidney-resident macrophages are considered to be involved in the pathogenesis of renal ischemia-reperfusion injury (IRI). Several subsets of monocytes and macrophages are localized in the injured tissue, but the pathologic roles of these cells are not fully understood. Here, we show that CD169⁺ monocytes and macrophages have a critical role in preventing excessive inflammation in IRI by downregulating intercellular adhesion molecule-1 (ICAM-1) expression on vascular endothelial cells. Mice depleted of CD169⁺ cells showed enhanced endothelial ICAM-1 expression and developed irreversible renal damage associated with infiltration of a large number of neutrophils. The perivascular localization of CD169⁺ monocytes and macrophages indicated direct interaction with blood vessels, and coculture experiments showed that the direct interaction of CD169⁺ cell-depleted peripheral blood leukocytes augments the expression levels of ICAM-1 on endothelial cells. Notably, the transfer of Ly6C^lo monocytes into CD169⁺ cell-depleted mice rescued the mice from lethal renal injury and normalized renal ICAM-1 expression levels, indicating that the Ly6C^lo subset of CD169⁺ monocytes has a major role in the regulation of inflammation. Our findings highlight the previously unknown role of CD169⁺ monocytes and macrophages in the maintenance of vascular homeostasis and provide new approaches to the treatment of renal IRI.     

Current Options and Emerging Biomaterials for Periprosthetic Joint Infection

Purpose of Review

Infection in the setting of total joint arthroplasty, referred to as periprosthetic joint infection (PJI), is a devastating complication requiring prolonged and costly treatment. The unique environment around an artificial joint and ability of surrounding tissues to sequester bacteria collectively make prevention, diagnosis, and treatment of this condition challenging. In light of the unique pathogenesis of PJI, this review explores the limitations of contemporary treatments and discusses novel treatment options.

Recent Findings

Recent advancements in local antibiotic delivery platforms for preventing and treating PJI include titanium nanotube arrays, synthetic polymers, resorbable hydrogels, and cyclodextrin-based drug delivery options. In particular, cyclodextrins have facilitated great advancements in other clinical disorders and have demonstrated early promise as a future option in the arena of PJI.

Summary

Novel treatment modalities for PJI optimize the implant surfaces to prevent bacterial biofilm formation or provide prolonged intra-articular antibiotic dosing to eradicate bacteria.

     

Gliadin effect on the oxidative balance and DNA damage: An in-vitro,ex-vivo study

Background

Gliadins are involved in gluten-related disorders and are responsible for the alteration of the cellular redox balance. It is not clear if the gliadin-related oxidative stress can induce DNA damage in enterocytes.

New predictors of outcome in idiopathic pulmonary arterial hypertension

Idiopathic pulmonary arterial hypertension (PAH) is a rare disease with a poor prognosis. New therapies have improved the outcome of this condition; accordingly, the factors that determine outcome may have changed. We aimed to identify determinants of survival in a cohort of consecutive patients with PAH: which was idiopathic, familial, or associated with anorexigen use. We performed a retrospective cohort study of 84 consecutive patients with PAH who underwent initial evaluation at our center from January 1994 to June 2002. The primary outcome was death or lung transplantation. Survival at 1, 3, and 5 [corrected] years was 87%, 75%, and 61%, respectively. Multivariate analysis showed that being of African-American or Asian descent was associated with an increased risk of death. Warfarin use was associated with a reduced risk of death. Higher serum albumin and cardiac index and acute vasoreactivity were independently associated with improved survival. These data suggest that the determinants of outcome have changed. Race is identified as a new risk factor, which may be attributable to biologic or socioeconomic differences. Cardiac function and acute reactivity of the pulmonary vascular bed remain strong independent predictors of outcome.     

Risk of severe liver disease in nonalcoholic fatty liver disease with normal aminotransferase levels: a role for insulin resistance and diabetes

It is uncertain whether patients with nonalcoholic fatty liver disease (NAFLD) and normal alanine aminotransferase (ALT) have a milder disease and should undergo liver biopsy. We reviewed the histological data of 458 Italian patients with NAFLD in whom liver biopsy was indicated by altered liver enzymes (395 cases, 86%), or persistently elevated ferritin or long-lasting severe steatosis (63 cases). Factors associated with nonalcoholic steatohepatitis (NASH) and fibrosis >/= 2 were identified by multivariate analysis. Patients with normal ALT were significantly older, had lower body mass index, fasting triglycerides, insulin resistance according to homeostasis model assessment (HOMA-IR), ALT, and gamma-glutamyltransferase, but a higher prevalence of hypertension. NASH was diagnosed in 59% and 74% of the patients with normal and increased ALT, respectively (P = 0.01). In the overall series of patients, NASH was independently predicted by ALT (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.04-1.19 per 10-IU/mL increase) and diabetes (OR, 1.5; 95% CI, 1.1-2.0). The same variables were selected in patients with increased ALT, whereas in those with normal ALT, HOMA-IR and ALT were independent predictors. Severe fibrosis was independently predicted by serum ferritin (OR, 1.04; 95% CI, 1.001-1.08 per 50-ng/mL increase), ALT (OR, 1.07; 95% CI, 1.02-1.14), and diabetes (OR, 1.8; 95% CI, 1.4-2.3) in the overall series, serum ferritin and diabetes in those with increased ALT, and only HOMA-IR (OR, 1.97; 95% CI, 1.2-3.7) in patients with normal ALT. CONCLUSION: Normal ALT is not a valuable criterion to exclude patients from liver biopsy. Alterations in glucose metabolism and insulin resistance in subjects with normal ALT should also be considered in the selection of NAFLD cases for histological assessment of disease severity and progression.